Ball-milled CuPc/TiO2 hybrid nanocomposite and its photocatalytic degradation of aqueous Rhodamine B

Hybrid composites of titanium dioxide and copper phthalocyanine were synthesized by ball-milling assisted process in combination with mechanically stirring method. Structural properties of as-synthesized composites were characterized by X-ray diffraction (XRD), X-ray absorption fine structure (XANES) and scanning electron microscope (SEM). The optical absorbance of as-prepared composites and their photocatalytic activities were investigated by UV–vis spectroscopy. XRD and XANES results confirm that CuPc/TiO2 nanocomposite is still in the same structure of TiO2 and CuPc. SEM result reveals that the decreasing particle size of ball-milled CuPc has good dispersion on the surface of TiO2. Absorptivity in UV region of the composites is heightened and shifted to visible light due to strong absorbance in blue-green spectrum of CuPc. The photocatalytic degradation of Rhodamine B dye solution using as-synthesized composites was investigated under ultraviolet irradiation. The optimized condition for RhB photodegradation was obtained for 1 wt.% CuPc/TiO2 nanocomposite with efficiency of 87.5% and reaction rate of 0.15 min−1. The significant improvement in photocatalytic activity of the hybrid composite may be associated to the enhancement of optical absorption and the inhibition of electron–hole recombination caused by the presence of CuPc in TiO2 matrix.

This work reports on the synthesis of hybrid composites of titanium dioxide and copper phthalocyanine via ball-milling assisted process in combination with mechanical mixing process. Their structural properties and photocatalytic degradation of aqueous RhB were investigated. The significant enhancement of the photocatalytic performance of the composite may be related to the charge recombination suppression guiding to the increase of free functional radicals participated in degradation process.Figure optionsDownload as PowerPoint slideHighlights
► CuPc/TiO2 nanocomposite was synthesized by ball-milling assisted process and mechanical mixing method.
► Ball milling process can reduce CuPc size and assist the formation of well-dispersed composite.
► Loaded CuPc has inconsiderable influence on basic crystal structure of TiO2 matrix.
► The optical absorption properties of TiO2 in UV and visible light is improved with the existence of CuPc.
► CuPc/TiO2 nanocomposite can efficiently heighten the catalytic performance of TiO2 in the photodegradation of RhB.